原文链接: https://leetcode-cn.com/problems/maximum-number-of-balloons 英文原文Given a string text, you want to use the characters of text to form as many instances of the word "balloon" as possible. You can use each character in text at most once. Return the…

原文链接: https://leetcode-cn.com/problems/reverse-substrings-between-each-pair-of-parentheses 英文原文You are given a string s that consists of lower case English letters and brackets. Reverse the strings in each pair of matching parentheses, starting from …

原文链接: https://leetcode-cn.com/problems/k-concatenation-maximum-sum 英文原文Given an integer array arr and an integer k, modify the array by repeating it k times. For example, if arr = [1, 2] and k = 3 then the modified array will be [1, 2, 1, 2, 1, 2]. R…

原文链接: https://leetcode-cn.com/problems/critical-connections-in-a-network 英文原文There are n servers numbered from 0 to n - 1 connected by undirected server-to-server connections forming a network where connections[i] = [ai, bi] represents a connection b…

原文链接: https://leetcode-cn.com/problems/reformat-department-table 英文原文Table: Department +-------------+---------+ | Column Name | Type | +-------------+---------+ | id | int | | revenue | int | | month | varchar | +-------------+---------+ (id, month)…

原文链接: https://leetcode-cn.com/problems/delete-characters-to-make-fancy-string 英文原文A fancy string is a string where no three consecutive characters are equal. Given a string s, delete the minimum possible number of characters from s to make it fancy. …

原文链接: https://leetcode-cn.com/problems/longest-happy-string 英文原文A string is called happy if it does not have any of the strings 'aaa', 'bbb' or 'ccc' as a substring. Given three integers a, b and c, return any string s, which satisfies following cond…

原文链接: https://leetcode-cn.com/problems/number-of-visible-people-in-a-queue 英文原文There are n people standing in a queue, and they numbered from 0 to n - 1 in left to right order. You are given an array heights of distinct integers where heights[i] repr…

原文链接: https://leetcode-cn.com/problems/ugly-number-iii 英文原文An ugly number is a positive integer that is divisible by a, b, or c. Given four integers n, a, b, and c, return the nth ugly number. Example 1: Input: n = 3, a = 2, b = 3, c = 5 Output: 4 Ex…

原文链接: https://leetcode-cn.com/problems/smallest-string-with-swaps 英文原文You are given a string s, and an array of pairs of indices in the string pairs where pairs[i] = [a, b] indicates 2 indices(0-indexed) of the string. You can swap the characters at …

原文链接: https://leetcode-cn.com/problems/sort-items-by-groups-respecting-dependencies 英文原文There are n items each belonging to zero or one of m groups where group[i] is the group that the i-th item belongs to and it's equal to -1 if the i-th item belong…

原文链接: https://leetcode-cn.com/problems/largest-magic-square 英文原文A k x k magic square is a k x k grid filled with integers such that every row sum, every column sum, and both diagonal sums are all equal. The integers in the magic square do not have to…

原文链接: https://leetcode-cn.com/problems/watering-plants 英文原文You want to water n plants in your garden with a watering can. The plants are arranged in a row and are labeled from 0 to n - 1 from left to right where the ith plant is located at x = i. The…

原文链接: https://leetcode-cn.com/problems/count-ways-to-build-rooms-in-an-ant-colony 英文原文You are an ant tasked with adding n new rooms numbered 0 to n-1 to your colony. You are given the expansion plan as a 0-indexed integer array of length n, prevRoom,…

原文链接: https://leetcode-cn.com/problems/fizz-buzz-multithreaded 英文原文You have the four functions: printFizz that prints the word "Fizz" to the console, printBuzz that prints the word "Buzz" to the console, printFizzBuzz that prints the word "FizzBuzz" …

原文链接: https://leetcode-cn.com/problems/unique-number-of-occurrences 英文原文Given an array of integers arr, return true if the number of occurrences of each value in the array is unique, or false otherwise. Example 1: Input: arr = [1,2,2,1,1,3] Output: t…

原文链接: https://leetcode-cn.com/problems/get-equal-substrings-within-budget 英文原文You are given two strings s and t of the same length. You want to change s to t. Changing the i-th character of s to i-th character of t costs |s[i] - t[i]| that is, the ab…

原文链接: https://leetcode-cn.com/problems/minimum-moves-to-reach-target-with-rotations 英文原文In an n*n grid, there is a snake that spans 2 cells and starts moving from the top left corner at (0, 0) and (0, 1). The grid has empty cells represented by zeros…

原文链接: https://leetcode-cn.com/problems/where-will-the-ball-fall 英文原文You have a 2-D grid of size m x n representing a box, and you have n balls. The box is open on the top and bottom sides. Each cell in the box has a diagonal board spanning two corner…

原文链接: https://leetcode-cn.com/problems/path-with-maximum-probability 英文原文You are given an undirected weighted graph of n nodes (0-indexed), represented by an edge list where edges[i] = [a, b] is an undirected edge connecting the nodes a and b with a …

原文链接: https://leetcode-cn.com/problems/sum-of-floored-pairs 英文原文Given an integer array nums, return the sum of floor(nums[i] / nums[j]) for all pairs of indices 0 <= i, j < nums.length in the array. Since the answer may be too large, return it modulo…

原文链接: https://leetcode-cn.com/problems/minimum-cost-to-move-chips-to-the-same-position 英文原文We have n chips, where the position of the ith chip is position[i]. We need to move all the chips to the same position. In one step, we can change the position…

原文链接: https://leetcode-cn.com/problems/longest-arithmetic-subsequence-of-given-difference 英文原文Given an integer array arr and an integer difference, return the length of the longest subsequence in arr which is an arithmetic sequence such that the diff…

原文链接: https://leetcode-cn.com/problems/path-with-maximum-gold 英文原文In a gold mine grid of size m x n, each cell in this mine has an integer representing the amount of gold in that cell, 0 if it is empty. Return the maximum amount of gold you can colle…

原文链接: https://leetcode-cn.com/problems/maximum-product-of-the-length-of-two-palindromic-substrings 英文原文You are given a 0-indexed string s and are tasked with finding two non-intersecting palindromic substrings of odd length such that the product of t…

原文链接: https://leetcode-cn.com/problems/design-skiplist 英文原文Design a Skiplist without using any built-in libraries. A skiplist is a data structure that takes O(log(n)) time to add, erase and search. Comparing with treap and red-black tree which has th…

原文链接: https://leetcode-cn.com/problems/the-dining-philosophers 英文原文Five silent philosophers sit at a round table with bowls of spaghetti. Forks are placed between each pair of adjacent philosophers. Each philosopher must alternately think and eat. Ho…

原文链接: https://leetcode-cn.com/problems/split-a-string-in-balanced-strings 英文原文Balanced strings are those that have an equal quantity of 'L' and 'R' characters. Given a balanced string s, split it in the maximum amount of balanced strings. Return the …

原文链接: https://leetcode-cn.com/problems/queens-that-can-attack-the-king 英文原文On an 8x8 chessboard, there can be multiple Black Queens and one White King. Given an array of integer coordinates queens that represents the positions of the Black Queens, an…

原文链接: https://leetcode-cn.com/problems/dice-roll-simulation 英文原文A die simulator generates a random number from 1 to 6 for each roll. You introduced a constraint to the generator such that it cannot roll the number i more than rollMax[i] (1-indexed) c…